What If-- a future sequel (part 3) offered some form of election intrigue-- perhaps they go with the Brubaker storyline where a charismatic third-party Presidential candidate becomes very popular, but is secretly backed by the Red Skull and/or Alexander Lukin. And of course, they are seeking Cap's endorsement, maybe offer him a vice-presidential role--

Maybe this is how John Walker gets introduced to the stories-- first as 'super-patriot': campaign "mascot" of the candidate (but he does not know of the corruption at hand), then as USAgent..

Also, there's the angle where Cap himself gets goaded into running for office as an independent.

There can be a subplot where the major-party candidates (fictional, of course) are seeking Cap's endorsement.. Meanwhile there is a plot of terrorism in the works by Flag Smasher, Ultimatum, and more..

There can be cameos from various real-world news personalities covering the action..